Angioplasty apparatus facilitating rapid exchange and method

ABSTRACT

Apparatus for introduction into the vessel of a patient comprising a guiding catheter adapted to be inserted into the vessel of the patient and a device adapted to be inserted into the guiding catheter. The device includes a flexible elongate member and a sleeve carried by the flexible elongate member near the distal extremity thereof and extending from a region near the distal extremity to a region spaced from the distal extremity of the flexible elongate element. The device also includes a guide wire adapted to extend through the sleeve so that the guide wire extends rearwardly of the sleeve extending alongside of and exteriorally of the flexible elongate element into a region near the proximal extremity of the flexible elongate element.

This is a continuation of patent application Ser. No. 07/937,977 filedon Nov. 2, 1992, which is a continuation of Ser. No. 07/774,479 filedOct. 10, 1991, abandoned, which was a continuation of Ser. No.07/548,200 filed Jul. 5, 1990, now U.S. Pat. No. 5,061,273, which was acontinuation of Ser. No. 07/361,676 filed Jun. 1, 1989, abandoned, whichwas a continuation of Ser. No. 07/117,357 filed Oct. 27, 1987,abandoned, which was a continuation of Ser. No. 06/852,197 filed Apr.15, 1986, abandoned.

This invention relates to angioplasty apparatus facilitating rapidexchanges and a method for making rapid exchanges of angioplastydevices.

At the present time in practicing angioplasty, it is often necessary toexchange one dilatation catheter for another. In doing so, it has beennecessary to utilize long exchange wires having a length ofapproximately 300 centimeters which typically requires two operators toperform the procedure. During this procedure, it is necessary that theoperators communicate with each other which makes the procedure timeconsuming. In addition, since the exchange wire is so long it often isawkward to handle and for that reason may come in contact with the flooror become contaminated which necessitates removing the entire apparatusbeing utilized for the angioplasty procedure. There is therefore a needfor a new and improved angioplasty apparatus which overcomes suchdifficulties.

In general, it is an object of the present invention to provide anangioplasty apparatus and a method which facilitates rapid exchanges ofvarious types of devices.

Another object of the invention is to provide an angioplasty apparatusand method of the above character which greatly facilitates exchanges ofdilatation catheters.

Another object of the invention is to provide an angioplasty apparatusand method of the above character which can be utilized for thepositioning of flexible elongate members.

Another object of the invention is to provide an angioplasty apparatusand method of the above character which can be utilized with varioustypes of devices utilizing flexible elongate members.

Another object of the invention is to provide an angioplasty apparatusand method in which dye injection and pressure measurements can be made.

Additional objects and features of the invention will appear from thefollowing description in which the preferred embodiments are set forthin conjunction with the accompanying drawings.

FIG. 1 is a side elevational view of an angioplasty apparatusincorporating the present invention.

FIGS. 2A, 3A and 4A are partial cross sectional views of the shaft,transition and balloon regions of the balloon dilatation catheterutilized in the embodiment of the invention shown in FIG. 1.

FIGS. 2B, 3B and 4B are cross sectional views taken along the lines2B--2B, 3B--3B and 4B--4B of FIGS. 2A, 3A and 4A respectively.

FIGS. 5A, 6A and 7A are cross sectional views corresponding to FIGS. 2A,3A and 4A of another embodiment of a balloon dilatation catheterincorporating the present invention.

FIGS. 5B, 6B and 7B are cross sectional views taken along the lines5B--5B, 6B--6B and 7B--7B of FIGS. 5A, 6A and 7A respectively.

FIGS. 8A and 9 are cross sectional views of the transition and balloonregions of another balloon dilatation catheter incorporating the presentinvention.

FIG. 8B is a cross sectional view taken along the line 8B--8B of FIG.8A.

FIG. 10 is a side elevational view of a dedicated dye injection/pressuremeasurement catheter incorporating the present invention.

FIG. 11 is a side elevational view of a fiber optic cable incorporatingthe present invention.

FIG. 12 is a side elevational view of a dedicated dye injection/pressuremeasurement catheter incorporating the present invention and havingspecific guiding means for facilitating entering acute bends in arterialvessels.

FIG. 13 is a side elevational view of a bail out catheter incorporatingthe present invention.

FIG. 14 is a plan view of a holder utilized in connection with thepresent invention.

In general, the angioplasty apparatus of the present invention isdesigned for introduction into the vessel of a patient. It consists of aguiding catheter which is adapted to be inserted into the vessel of thepatient. It also consists of a device which is adapted to be insertedinto the guiding catheter. The device includes a flexible elongatemember, a sleeve is secured to the flexible elongate member near thedistal extremity thereof and extends from the distal extremity into aregion spaced from the distal extremity of the flexible elongate member.The device also includes a guide wire which is adapted to extend throughthe sleeve from the distal extremity of the flexible elongate element,through the sleeve and rearwardly of the sleeve alongside of andexteriorally of the flexible elongate element.

More particularly as shown in FIGS. 1-4, the angioplasty apparatus 16for facilitating rapid exchanges of dilatation catheters consists of aconventional guiding catheter 17 which is provided with a rotatablehemostatic adapter 18 mounted on a proximal end and a y or two-armconnector or adapter 19 which is mounted on the rotatable adapter 18.The y-connector 19 is provided with a knurled knob 21 which carries athreaded valve member 22 that carries an O-ring 23 which is adapted tobe urged into sealing engagement with a balloon dilatation catheter 26and a guide wire 27 extending through the y-adapter 19 and through theguiding catheter 17 as shown in FIG. 1.

The balloon dilatation catheter 26 is of a single lumen type and isprovided with a flexible elongate tubular member 29 which has a lumen 31extending therethrough. The flexible tubular member 29 can be formed ofa suitable material such as plastic. A Luer-type fitting 32 is mountedon the proximal extremity of the flexible tubular member 29 and isadapted to be connected to a syringe or other type of instrument forintroducing a radiographic contrast liquid into the flexible tubularmember 29. A balloon 33 is mounted on the distal extremity of anotherflexible tubular member 36 also is formed of a suitable material such asplastic. The distal extremity of the balloon 33 is bonded to the distalextremity of the flexible tubular member 36 to form an air-tight andliquid-tight seal with respect to the same. The balloon 33 is coaxialwith the tubular member 36 or sleeve as shown in FIG. 4B. The flexibletubular member 36 is provided with a guide wire lumen 37 through whichthe guide wire 27 carrying its flexible tip 28 can extend.

Means is provided for forming a balloon inflation lumen 41 substantiallyconcentric with the flexible tubular member 36 and extends toward thedistal extremity of the flexible tubular member 36. As can be seen fromFIGS. 3B and 4B, the balloon inflation lumen 41 is formed by a flexibletubular member 42 which can be formed integral with the balloon 33. Theflexible tubular member 42 extends into a transition region 44 whichoverlies the distal extremity of the flexible tubular member 29 so thatthe lumen 31 therein is in communication with the balloon inflationlumen 41. As can be seen particularly from FIG. 3A, the flexible tubularmember 36 makes a transition and extends out of the tubular member 42and provides an opening 43. The proximal extremity of the tubular member36 overlies the flexible tubular member 31. The guide wire 27 exitsthrough the opening 43 and extends alongside and exteriorally of theflexible tubular member 29 from the proximal extremity of the flexibletubular member 36 to the proximal extremity of the flexible tubularmember 29.

The transition region 44 should be positioned at least approximately10-15 centimeters from the distal extremity of the balloon dilatationcatheter 26. This is important for two reasons. One is that thetransition region be kept at a point where when the balloon dilatationcatheter 26 is utilized in a procedure, the transition region remains inthe guiding catheter 27 and out of the coronary artery. The spacing fromthe distal extremity of the dilatation catheter for the transitionregion is also advantageous in that it permits the person performing theprocedure to pull the balloon dilatation catheter 26 out of the guidingcatheter 17 until the transition region 44 clears the y-connector 19 sothat all of the portion of the guide wire 27 which is exterior of theballoon dilatation catheter 26 is proximal of the y-connector. Whilethis is being done, the operator can then utilize the knurled nut 21 toagain close the O-ring to form a hemostatic seal between the y-connectorand the balloon dilatation catheter to minimize the loss of blood fromthe patient.

The flexible tubular member 42 can be formed of a suitable material suchas a heat shrinkable plastic so that it can be shrunk onto the distalextremity of the flexible tubular member 29 and onto the proximalextremity of the flexible tubular member 36 to form liquid-tight andair-tight seals with respect to the same. From the construction shown itcan be seen that the guide wire 27 exits from the balloon dilatationcatheter 26 in a region which is relatively close to the distalextremity of the balloon dilatation catheter 26 and extends exteriorallyof the balloon dilatation catheter to the proximal extremity of thesame. As shown in FIG. 1, the guide wire 27 and the balloon dilatationcatheter 26 extend outwardly from the y-connector 19.

A torquer 46 of a conventional construction is secured to the guide wire27 for rotating the guide wire as hereinafter described.

Operation and use of the angioplasty apparatus shown in FIG. 1 may nowbe briefly described as follows. The guiding catheter 17 is insertedinto the coronary artery in a conventional manner. The balloondilatation catheter is prepared for insertion into the guiding catheter17 in a conventional manner. The balloon 33 can be inflated outside thebody by the use of a balloon flushing tube of the type described in U.S.Pat. No. 4,323,071 and inflated by introducing a radiopaque liquidthrough the fitting 32 into the lumen 31 and through the lumen 41 intothe balloon 33 to flush all of the air in the balloon 33 through theballoon flushing tube to fully inflate the balloon. After the balloon 33has been inflated, the balloon can be deflated by removing theradiopaque liquid from the balloon.

The guide wire 27 is then introduced into the balloon dilatationcatheter 26 by a back loading technique. Without the torquer 46 on theguide wire, the proximal extremity of the guide wire 27 is insertedbackwardly through the tip of the balloon dilatation catheter throughthe guide wire lumen 37. The guide wire is advanced rearwardly byholding the distal extremity of the balloon dilatation catheter in onehand and advancing the guide wire 27 rearwardly with the other handuntil the guide wire 27 exits through the opening 43 at the transitionregion 44 of the dilatation catheter. As soon as the guide wire hascleared the opening 43, the guide wire can be grasped by the hand andpulled rearwardly paralleling the balloon dilatation catheter 26 untilits proximal extremity is near the proximal extremity of the dilatationcatheter and so that the distal extremity of the guide wire 27 with itsflexible or floppy tip 28 protrudes at least partially from the distalextremity of the balloon dilatation catheter.

At this point in time, the O-ring 23 in the y-connector 19 is opened byoperation of the knurled knob 21. The distal extremity of the balloondilatation catheter 26 having the flexible tip protruding therefrom isthen introduced to the y-connector past the opened O-ring 23 and sliddown the guiding catheter 17. The balloon dilatation catheter 26 and theguide wire 27 are grasped between the fingers of a hand and are advancedparallel into the guiding catheter 17. This procedure is continued untila substantial portion of the balloon dilatation catheter is disposed inthe guiding catheter 17.

The torquer 46 now can be attached to the guide wire 27 near theproximal extremity of the same. The guide wire 27 is then advanced aheadof the balloon dilatation catheter until it enters the arterial vesselof the patient. The balloon dilatation catheter 26 is held stable by thefingers of the hand while the guide wire 27 is being advanced. Thepositioning of the guide wire 27 in the desired arterial vessel can beobserved under a fluoroscope by using x-ray techniques well known tothose skilled in the art. As is well known to those skilled in the art,the torquer 46 can be utilized for rotating the guide wire 27 tofacilitate positioning of the flexible tip 28 in the desired arterialvessel so that the distal extremity of the guide wire can be advancedinto the stenosis which it is desired to open or enlarge.

As soon as the guide wire 27 is in the desired location, it can be heldstationary by two fingers of the hand and at this point in time, theballoon dilatation catheter 26 is advanced over the guide wire until thedeflated balloon 33 is across the desired lesion or stenosis. If anydifficulty is encountered by the person conducting the procedure inintroducing the balloon dilatation catheter so that the balloon 33resists crossing the lesion or stenosis, the guide wire 27 can beretracted slightly. The person then can observe under the fluoroscope tosee that the tip 28 of the guide wire is wiggling in the blood streamindicating that it is free to move in the blood stream. Then the personcan grasp both the guide wire and the dilatation catheter in one handand advance them as a unit so that they can cross the stenosis as aunit. It has been found by utilizing such a procedure, greaterpushability can be obtained in advancing the balloon dilatation catheteracross the stenosis. In other words, more force can be applied to theballoon to cause it to cross the stenosis or lesion in case the openingtherein is very small.

After the balloon 33 has crossed the stenosis or lesion, the balloon 33can be inflated in a conventional manner by introducing a radiopaquecontrast liquid through the lumen 31. After the inflation has occurredand the desired operation has been performed by enlarging the opening inthe stenosis, the balloon dilatation catheter 26 can be removed veryrapidly by the person performing the procedure by grasping the guidewire 27 by two fingers immediately proximal of the y-connector 19 afterthe torquer 46 has been removed. The balloon dilatation catheter 26 canbe removed in several seconds in comparison with the much longer timerequired for removing the balloon dilatation catheter utilizing priorart exchange wire procedures. As soon as the balloon dilatation catheter26 has been removed from the guiding catheter 17, another injection ofradiographic contrast liquid can be introduced through the guidingcatheter 17 to observe whether or not the balloon dilatation procedurewhich has been performed on the lesion or stenosis has in fact openedthe lesion or stenosis to the satisfaction of the person performing theprocedure.

If it is ascertained by the person performing the procedure thatadditional dilation of the stenosis is desired and that a larger balloonshould be inserted into the stenosis, this can be accomplished veryrapidly by selecting the desired size of balloon dilatation catheter.

As the balloon dilatation catheter 26 is being retracted out of theguiding catheter 17 and as soon as the transition region 44 has clearedthe y-adapter 19, the O-ring 23 can be tightened down to form a sealover the balloon dilatation catheter to minimize the loss of blood ofthe patient. Thereafter, if desired, the remainder of the balloondilatation catheter 26 can be removed from the guiding catheter 17 untilthe proximal extremity of the guide wire passes through the opening 43and passes through the end of the balloon dilatation catheter 26. Assoon as this has been accomplished, a new balloon dilatation cathetercan be loaded onto the guide wire in a rearward direction by introducingthe proximal extremity of the guide wire 27 into the tip of the balloondilatation catheter. As this is being done, the index finger of the handperforming the procedure can be utilized for opening the O-ring byadjusting the knurled knob 21. The guide wire 27 is grasped by thefingers of the hand and the balloon dilatation catheter 26 can beadvanced rapidly over the guide wire into the guiding catheter 17 andadvanced across the lesion in a manner hereinbefore described withrespect to the smaller balloon dilatation catheter which had beenutilized. The balloon of the new dilatation catheter can be inflated inthe same manner as hereinbefore described. If necessary even anotherexchange procedure can be readily accomplished in the same manner ashereinbefore described utilizing a still larger balloon dilatationcatheter if that turns out to be necessary.

It has been found that an exchange utilizing the present angioplastyapparatus can be performed in less than 10 to 15 seconds whereas in thepast utilizing a prior art guide wire exchange procedure required anaverage of approximately two minutes.

After the desired amount of dilation of the stenosis or lesion has beenaccomplished, the balloon dilatation catheter 26 can be removed andthereafter, the guiding catheter 17 can be removed.

Another embodiment of an angioplasty apparatus incorporating the presentinvention is shown in FIGS. 5A and 5B, 6A and 6B and 7A and 7B in whichan additional dye/pressure lumen has been incorporated into theapparatus in order to enable an injection of a distal dye through theballoon dilatation catheter and also to enable the measurement ofpressures at the tip of the balloon dilatation catheter. Theconstruction which is utilized is very similar to that shown in theballoon dilatation catheter 26 shown in FIG. 1. The corresponding partsof the balloon dilatation catheter 26a shown in FIGS. 5-7 is verysimilar to that hereinbefore described and for that reason thecorresponding parts have been given the same corresponding numbers withletters being added to the numerals where changes are present in theparts or components. Thus the tubular member 29a, rather than having asingle lumen 31 is provided with dual lumens 31a and 31b disposed sideby side in the shaft region of the balloon dilatation catheter as shownin FIGS. 5A and 5B. In the transition region 44a, the two lumens 31 aand 31b are still disposed side by side with the lumen 37a for the guidewire being disposed above the lumens 31a and 31b. In the balloon region,the lumen 31a has been terminated and extends into the balloon lumen41a. At the transition region 44a, the guide wire lumen 37a inclinesdownwardly and sidewise and adjoins the lumen 31b through the distalextremity of the balloon dilatation catheter 26a. The lumen 31b extendsto the distal extremity of the balloon dilatation catheter.

The balloon dilatation catheter which is shown in FIGS. 5-7 can beutilized in the same manner as the balloon dilatation catheter shown inFIG. 1. It can be seen that the guide wire 27 extends out of the opening43a in the transition region 44c and parallels the balloon catheter toits proximal extremity. A balloon dilatation catheter of the type shownin FIGS. 5-7 can be utilized initially in an angioplasty procedure.However, it should be appreciated that if a very small opening ispresent in the stenosis or lesion, it may be desirable to utilize aballoon dilatation catheter of the type shown in FIG. 1 first because itcan be constructed with a smaller diameter than a balloon dilatationcatheter of the type shown in FIGS. 5-7 because of the additional lumenwhich is provided for dye injection and pressure measurements. After asmaller balloon dilatation catheter has been utilized, a balloondilatation catheter of the type shown in FIGS. 5-7 can be used utilizingthe exchange procedure hereinbefore described to make dye injectionand/or pressure measurements through the use of the additional lumen31b. It is particularly desirable to make such a pressure measurementbefore conclusion of the angioplasty procedure to be sure that theproper dilation of the lesion or stenosis has occurred and that there isadequate blood flow through the lesion or stenosis.

Still another embodiment of the angioplasty apparatus incorporating thepresent invention is shown in FIGS. 8A and 8B and shows the transitionregion of a balloon dilatation catheter 26b which incorporates a venttube 51 which is utilized for venting air from the balloon duringinflation of the balloon and before insertion into the patient withradiopaque liquid to ensure that all the air is exhausted from theballoon. As shown in the transition region 44b in FIG. 8A, the guidewire 27 extends through an opening 43b provided in the transition regionand extends through a flexible tubular member 36b out the end of theballoon dilatation catheter as shown in FIG. 9. A balloon filling lumen31c is provided by the flexible tubular member 29b and terminates in thetransition region 44b where it opens into the balloon filling lumen 41bthat opens into the interior of the balloon 33b. A relatively shortsleeve 52 formed of a suitable material such as plastic is also providedin the transition region 44b and as shown in FIG. 8A underlies theflexible tubular member 29b and extends from a region forward of theflexible tubular member 42b and terminates distally within the ballooninflation lumen 41 as shown in FIG. 8A.

The sleeve 52 is provided with a lumen 53 through which the vent tube 51extends. The vent tube 51 can be formed of a suitable material such asmetal and is also provided with a lumen 54 of a size so that gas canescape therethrough. The proximal extremity of the vent tube 51 isprovided with a portion 51a which is bent at right angles to the mainportion of the vent tube 51 to ensure that the vent tube will be removedfrom the balloon dilatation catheter 26b prior to insertion into theguiding catheter 17. As shown in FIG. 9, the vent tube 51 extends intothe balloon 33 into a region near the distal extremity of the same.

Operation of the balloon dilatation catheter 26b shown in FIGS. 8A, 8Band 9 may now be briefly described as follows. With the vent tube 51 inplace in the balloon dilatation catheter, radiopaque contrast liquid isintroduced through the balloon inflation lumen 31 and through theballoon inflation lumen 41b to introduce the liquid into the balloon. Asthe liquid is introduced into the balloon, any air in the balloon isdischarged through the vent tube 51. Pressure is maintained on theradiopaque contrast liquid introduced into the balloon until droplets 56of the liquid exit from the proximal extremity of the vent tube 51 whichserves to indicate that the balloon has been completely filled with theradiopaque contrast liquid and that all of the air therein has beenexhausted therefrom. As soon as this occurs, the vent tube 51 can bewithdrawn completely from the balloon dilatation catheter. The sleeve 52which carries the vent tube collapses upon withdrawal of the vent tubeand will remain collapsed to provide a valve to prevent the escape ofany additional radiopaque contrast liquid from the balloon 33b. Thesleeve 52 remains collapsed because when a high pressure is beingintroduced through the balloon inflation lumen 31c, the flexible tubularmember 29b will force collapsing of the sleeve 52. Alternatively, when anegative pressure is being applied to the balloon 33b as, for example,when the balloon is being deflated, the positive atmospheric pressure onthe exterior of the flexible tubular member 42 b will again causecollapsing of the sleeve 52. Thus in effect there is provided a doublevalve system in which positive pressures on the interior will collapsethe sleeve and when there is negative internal pressure the positiveexterior atmospheric pressure will collapse the sleeve.

In all other respects, the balloon dilatation catheter 26b can beutilized in the same manner as the balloon dilatation cathetershereinbefore described in connection with exchanges on the guide wire27.

Still another embodiment of an angioplasty apparatus incorporating thepresent invention is shown in FIG. 10 in which there is disclosed adedicated pressure/dye catheter 61. The pressure/dye catheter 61consists of an elongate flexible tubular member 62 formed of a suitablematerial such as plastic which is provided with a pressure dye lumen 63extending therethrough. The proximal extremity of the tubular member 62is provided with a Luer-type fitting 64 to which devices havingLuer-type fittings can be attached. A sleeve 66 formed of a suitablematerial such as plastic is secured to the exterior of the flexibletubular member 62 by suitable means such as an adhesive. It is providedwith a guide wire lumen 67 extending therethrough. It should beappreciated that the sleeve 66 can be formed integral with the flexibletubular member 62 if desired. The sleeve 66 extends for a distance of atleast 10 to 15 centimeters from the distal extremity of the catheter 61so that the transition region where it terminates at its proximalextremity is be within the guiding catheter 17 so that the transitionregion does not enter into the arterial vessel of the patient. A guidewire 68 is provided which extends through the guide wire lumen 67. Theguide wire can be of the same type as the guide wire 27. It is insertedinto the sleeve 66 by taking the proximal extremity of the guide wirewhich is relatively stiff and inserting it into the distal extremity ofthe sleeve and then pushing it backwardly or rearwardly through thesleeve until it clears the opening 69 at the proximal extremity of thesleeve The guide wire 68 is then pulled so that it extends in adirection parallel to the flexible tubular member 62 into a region nearthe proximal extremity of the tubular member

It can be readily seen from the foregoing description that thepressure/dye catheter 6 can be readily introduced into a guidingcatheter 17 and that the distal extremity of the pressure/dye cathetercan be positioned in a desired location in the arterial vessel byutilizing the guide wire 68 to position the same. It also should beappreciated that a torquer of the type hereinbefore described such asthe torquer 46 can be utilized on the proximal extremity of the guidewire 68 to cause rotational movement of the guide wire to facilitatepositioning of the guide wire in the desired arterial vessel and tothereafter have the tubular member 62 follow the same. The desiredpicture and/or dye measurements can then be made by utilizing the lumen63 provided in the tubular member 62. As can be seen from FIG. 10 thedistal extremity of the tubular member 62 can be slanted and rounded asshown to facilitate entry into the stenosis in the arterial vessel. Thisis desirable because of the eccentricity created by the addition of thesleeve 66.

Another embodiment of an angioplasty apparatus is shown in FIG. 11 andtakes the form of a fiber optic device 71. An encased fiber optic bundle72 which is generally circular in cross-section is provided. A sleeve 73of the type hereinbefore described formed of a suitable material such asplastic is secured to the distal extremity of the fiber optic bundle 72which is adapted to receive a guide wire 74. As in the previousembodiments, the sleeve 73 extends from the distal extremity for adistance of approximately 10 to 15 centimeters after which the guidewire exits from the sleeve and extends alongside and exteriorally of thefiber optic bundle 72 for substantially the entire length of the fiberoptic bundle. As with the previous devices, the guide wire 74 isthreaded into the sleeve by taking the proximal extremity or stiff endof the guide wire and inserting it at the distal extremity of the sleeve73 and pushing it from the rear towards the forward extremity of thesleeve. The fiber optic device 71 can then be inserted into a guidingcatheter 17 and advanced to the desired location through the use of theguide wire. The fiber optic bundle then can be utilized for angioscopyfor looking directly at the blood vessel or alternatively, fordelivering energy to plaque in the blood vessel to perform laserangioplasty. It should be appreciated that steerable systems can beutilized for directing the distal extremity of the fiber optic bundle ifthat is desired.

It should be appreciated that the concept of using a relatively shortsleeve extending from the distal extremity of the device to a regionapproximately 10 to 15 centimeters to the rear and then having the guidewire extend externally of the device is applicable for a number ofmedical devices as well as other applications. For example, ultrasoniccatheters 26a for imaging ultrasound and for measurement of Dopplervelocity 16a can be utilized to provide various types of dedicateddevices having the guide sleeve with the guide wire therein forfacilitating positioning of the same in arterial vessels. The apparatusof the present invention is particularly useful in devices wheremultiple re-entries are required in order to complete the procedure.

In FIG. 12, there is disclosed another embodiment of an angioplastyapparatus to provide a pressure dye catheter 76 having additionalsteering capabilities. It consists of a flexible tubular member 77formed of a suitable material such as plastic which is provided with alumen 78 extending through a slanted and curved end. A Luer-type fitting79 is provided on the proximal extremity. A sleeve 81 formed of asuitable material such as plastic is secured to the distal extremity ofthe flexible elongate member 77. The sleeve is provided with a curvedportion which extends slightly beyond the distal extremity of theflexible elongate member 77 and curves over the end of the flexibleelongate member 77. The guide wire 82 extends through the sleeve 81 asshown. The catheter shown in FIG. 12 can be utilized in situations wherethere is an acute bend in the arterial vessel. By using the cathetershown in FIG. 11, the guide wire can be directed into the acute bend byrotation of the catheter 76 to help direct the guide wire into the acutebend. After the acute bend has been negotiated by the guide wire, thedistal extremity of the catheter can follow the guide wire and negotiatethe acute bend. The desired pressure and/or dye measurements can then bemade. If by chance a guide wire should enter the wrong vessel, the guidewire can be retracted into the sleeve and then the catheter itself canbe reoriented to have the distal extremity of the sleeve 81 directedinto the proper region so that the guide wire will enter the properarterial vessel. The catheter 76 shown in FIG. 12 can be introduced intothe guiding catheter 17 in the same manner as the other cathetershereinbefore described.

Still another embodiment of the angioplasty apparatus of the presentinvention is shown in FIG. 13 in the form of a bailout catheter 86. Thebailout catheter 86 consists of a flexible tubular member 87 formed of asuitable material such as plastic which is provided with a lumen 88extending therethrough. A Luer-type fitting 89 is secured to theproximal extremity of the tubular member 87. The distal portion of thetubular member 87 is provided with two sets 91 and 92 of holes 93 whichare spaced circumferentially and apart longitudinally of the tubularmember. A sleeve 96 formed of a suitable material such as plastic issecured to the distal extremity of the tubular member 87 and extendsfrom the distal extremity of the tubular member 87 into a region 10 to15 centimeters from the distal extremity and is adapted to receive aguide wire 97 which extends through the same. The guide wire 97 isinserted into the sleeve by taking the proximal extremity of the guidewire and inserting it into the distal extremity of the sleeve andpushing it rearwardly into the sleeve until it exits from the sleeve.The guide wire 97 is then pulled in a direction generally parallel tothe flexible tubular member 87 until it is adjacent the fitting

The bailout catheter 86 is utilized in situations where an obstructionhas occurred in a blood vessel and stops the flow of blood. In order toreestablish the flow of blood, the bailout device is inserted into theguiding catheter 17. If a guide wire is already in place, the bailoutdevice can be placed on the guide wire by introducing the proximalextremity of the guide wire into the sleeve and then pushing the bailoutcatheter on the guide wire into the guiding catheter 17 until it passesthrough the obstruction in the arterial vessel. The distal extremity ofthe bailout device is so positioned so that the obstruction is disposedbetween the two sets of holes 91 and 92. When the bailout catheter ispositioned, blood can still flow through the holes 93 past theobstruction which is held out of the way by the bailout catheter.

Thus it can be seen that the same principle utilizing a guide tube andan external guide wire passing through the guide tube can be utilizedfor positioning the bailout device. As pointed out previously, thebailout device can be utilized for positioning other types of devices inarterial vessel, as for example, atherectomy devices particularly wheremultiple re-entries or reintroductions of the devices are required.

In FIG. 14 there is disclosed additional angioplasty apparatus in whicha holder 101 is provided which serves as a support structure for ay-type connector 19 of the type hereinbefore described in conjunctionwith the angioplasty apparatus shown in FIG. 1. The holder 101 consistsof a rectangular member 102 which is generally planar. The member 102can be formed of a suitable material such as plastic and is providedwith a plurality of rectangular openings 103 extending longitudinally ofthe same to lighten the same. Posts 104 are provided on the forwardextremity of the member 102 and are adapted to receive the y-typeconnector 19 and to hold it in place on the member 102. When positionedin the posts 104, the knurled knob 21 extends into one of the openings103 so that it can be readily operated. A block 107 is carried by theother end of the member 102 and, if desired, can be formed integraltherewith. The block is provided with a plurality of spaced apart slots108 which are adapted to frictionally engage and receive the guide wire27. The friction block 107 should be positioned a suitable distance as,for example, 15 to 20 centimeters from the O-ring carried by they-connector 19.

Use of the holder 101 shown in FIG. 14 may now be briefly described asfollows. The holder 101 can be placed on the operating table near theregion where the guiding catheter 17 has been inserted into the patient,as for example, in a femoral artery in the leg of a patient. After theguide wire has been inserted into the guiding catheter, the proximal endor, in other words, the stiff end of the guide wire can be placed in thefriction clamp 108. When it is desired to utilize a dilatation catheter,the end of the guide wire which has been positioned in the clamp can belifted out of the slot 108 and inserted into the sleeve carried by thedistal extremity of the dilatation catheter by taking the proximal endand advancing it from the tip rearwardly through the sleeve. As soon asthe guide wire has been introduced through the sleeve, the proximalextremity of the guide wire can be repositioned in the slot 108.Thereafter, the dilatation catheter can be advanced independentlywithout the operator needing to pay any attention to the guide wirewhich is held in the desired position by the holder 101. similarly, theholder can be utilized to keep the guide wire in place while thedilatation catheter is being briskly withdrawn.

More than one of the slots 108 has been provided in the holder 101 inorder to make it possible to accommodate two wire or two balloondilatation catheters in which one of the other slots 108 can be utilizedfor accommodating the additional guide wire. This prevents the guidewires from becoming entangled with each other.

It is apparent from the foregoing that there has been provided anangioplasty apparatus which greatly facilitates the exchange of deviceswhich utilize flexible elongate elements as a part thereof. Rapidexchanges are possible with only one person being necessary to make theexchanges. The need for long exchange wires has been eliminated. Onedevice can be readily substituted for another utilizing the same guidewire which has already been positioned. It can be seen from theforegoing that a relatively simple and expedient solution has beenprovided which eliminates the need for long exchange wires and thedanger of those exchange wires becoming contaminated.

Although the present invention has been described principally inconjunction with catheters having coaxial lumens, it should beappreciated that the invention is as applicable, if not more applicable,to catheters having side-by-side lumens.

What is claimed is:
 1. An elongated ultrasound imaging catheter which isadapted to be inserted over a guidewire through a patient's blood vesselto perform diagnostic procedures therein, comprising:a) an elongatedcatheter body having an inner lumen extending therethrough, a proximalportion which is adapted to extend out of the patient, and a distalportion which is adapted to be disposed entirely within the patient'svascular system during diagnostic procedures and which has a transitionregion with a proximal port therein opening to the exterior of thecatheter and located at least 10 centimeters proximally from a distalport in the distal tip of the catheter body and a substantial distancedistally from the proximal portion of the catheter body which extendsout of the patient; b) an ultrasound imaging device at the distalportion of the catheter body which is distal to the proximal port; andc) an open ended tubular member fixed with respect to the catheter bodyand having an inner lumen which is substantially shorter than thecatheter body, which is disposed substantially in its entirety withinthe distal portion of the catheter body and which extends proximallywithin the catheter body from the distal port at the distal tip of thecatheter body to the proximal port in the transition region, said innerlumen of the tubular member adapted to slidably receive a guidewiretherein so that a distal portion of the guidewire extends distally outof the distal port and a proximal portion thereof extends proximally outof the proximal port to the exterior of the catheter body and generallyparallel and exteriorly to the catheter body over most of the length ofthe guidewire and out of the patient.
 2. An elongated catheter assemblyfor performing an ultrasound imaging procedure within a patient'sarterial system, which assembly includes a guiding catheter adapted tobe positioned within a patient's arterial system with the proximal endthereof extending out of the patient during the procedure, an ultrasoundimaging catheter adapted to be positioned within the inner lumen of theguiding catheter with the proximal end thereof extending out of theproximal end of the guiding catheter during the procedure and aguidewire adapted to be positioned within an inner lumen of theultrasound imaging catheter during the procedure, comprising:a) anelongated catheter body having a lumen which extends therein, a proximalportion which is adapted to extend out of the proximal end of theguiding catheter during an ultrasound imaging procedure, and a distalportion which is adapted to extend partially out of the distal end ofthe guiding catheter into the patient's artery during an ultrasoundimaging procedure and which has a distal port in the distal end thereof,a transition region in the distal portion which is adapted to remainwithin the inner lumen of the guiding catheter during an ultrasoundimaging procedure and which has a proximal port therein disposed asubstantial distance distally from the proximal portion which extendsout the proximal end of the guiding catheter, and at least 10centimeters proximally from the distal port; b) a relatively shorttubular member fixed with respect to the distal portion of the catheterbody having an inner lumen which is adapted to slidably receive theguidewire therein and which extends through the interior of the distalportion of the catheter body between the proximal port and the distalport, with a distal portion of the guidewire extending out the distalport and a proximal portion of the guidewire extending out of theproximal port and generally parallel and exteriorly to the catheter bodywithin the inner lumen of the guiding catheter; and c) an ultrasoundimaging device located at the distal portion of the catheter body distalto the proximal port.
 3. A catheter assembly for performing anintravascular procedure in a human patient, wherein the assembly isadapted to be disposed during the procedure within an inner lumen of anelongated guiding catheter which has a distal end inserted into anostium of the patient's coronary artery and a proximal end extending outof the patient, said assembly comprising:a) an elongated catheter whichis adapted to extend out of the distal end and the proximal end of theguiding catheter during the intravascular procedure, said cathetercomprising an elongated catheter body, the catheter body having a first,relatively long inner lumen extending from the proximal end to thedistal end of the catheter body, and a second inner lumen, much shorterthan the first inner lumen, which is defined at least in part by atubular member fixed with respect to the catheter body and extendsthrough the interior of the first inner lumen between a distal port atthe distal end of the catheter body and a proximal port disposed atleast 10 centimeters proximally from the distal port and a substantialdistance distally from the portion of the catheter which extends out ofthe proximal end of the guiding catheter so that the proximal port isadapted to remain within the guiding catheter during the intravascularprocedure; and b) an elongated guidewire which is disposed within thesecond inner lumen of the catheter body and which has a distal portionadapted to extend out of the distal port and a proximal portion adaptedto extend out of the proximal port, generally parallel and exteriorly tothe portion of the catheter body disposed within the guiding catheterand out the proximal end of the guiding catheter, and wherein saidelongated catheter is an ultrasound imaging catheter.
 4. A method ofexchanging a catheter in an intravascular procedure within a patient'scoronary artery wherein a guiding catheter having proximal and distalends and having an inner lumen extending therein is disposed within apatient's cardiovascular system with the distal end seated within anostium of the patient's coronary artery and a proximal end extending outof the patient, wherein a guidewire is disposed within the guidingcatheter with the distal end of the guidewire extending out the distalend of the guiding catheter into the coronary artery of the patient andthe proximal end of the guidewire extending out the proximal end of theguiding catheter which extends out of the patient and wherein a firstintravascular catheter with proximal and distal ends having an elongatedcatheter body, a first elongated inner lumen, and a second much shorterinner lumen having a distal port located in the distal end of thecatheter and a proximal port located at least about 10 centimeters fromthe distal end of the catheter and a substantial distance from theproximal end of the catheter is disposed within the guiding catheterwith the guidewire passing through the second inner lumen, the methodcomprising:a) withdrawing the first intravascular catheter disposedwithin the guiding catheter from the patient over the guidewire andremoving the catheter from the proximal end of the guidewire; b)providing a second intravascular catheter with proximal and distal endshaving an elongated catheter body, a first elongated inner lumenextending within the catheter body and a second much shorter inner lumenwhich extends through a distal portion of the catheter body, which has adistal port located in the distal end of the catheter and a proximalport located at least about 10 centimeters from the distal end of thecatheter and a substantial distance from the proximal end of the secondcatheter; c) directing the proximal end of the guidewire proximallythrough the distal port, through the second inner lumen and out theproximal port of the second catheter; and d) advancing the secondcatheter over the guidewire into and within the patient's vascularsystem until the distal end of the catheter is disposed within a desiredregion within the patient's vascular system with the proximal portremaining disposed within the guiding catheter, andwherein the secondcatheter is an ultrasound imaging catheter.